1. Field of the Invention
The present invention relates to recording material and, more particularly, it relates to recording material which may be used in common for various output printing machines widely used for business and home uses such as ink-jet printing machines, PPC machines and direct thermal transfer printing machines.
2. Prior Art
Hitherto, various kinds of recording paper have been developed depending on the kinds of printing machines such as direct thermal transfer printing machines, PPC machines, pen plotters and ink-jet printing machines. For example, for the use in ink-jet printing, though ordinary paper may be used for this printing method, there have been proposed various kinds of recording paper provided with ink-receiving layers which consist of porous layers or comprise water-soluble resins such as polyvinylpyrrolidone, polyvinyl alcohol and gelatin. Such recording paper for ink-jet printing must have good ink absorbency and water resistance and therefore there has been proposed recording paper of which ink receiving layer comprises a graft copolymer and/or a block copolymer so that it satisfies the both requirements of water absorbency and water resistance (Japanese Patent Un-examined Publication (KOKAI) No. 61-217280).
However, polymerization for preparing such a block co-polymer is a troublesome task and, moreover, the performance of resulting copolymers could not be completely sufficient.
There have been also proposed various kinds of recording paper other than the ones mentioned above in order to satisfy the requirements of water absorbency and water resistance, for example, those utilizing, as the resin contained in the ink-receiving layer, hydrophilic polyvinylpyrrolidone (hereinafter referred as "PVP") and an acidic component of (meth)acrylic polymers (Japanese Patent Un-examined Publication (KOKAI) No. 62-218181) or specific (meth)acrylic polymers (Japanese Patent Un-examined Publication (KOKAI) Nos. 62-222884 and 63-173678). However, those utilizing (meth)acrylic polymers alone have drawbacks, i.e., bad ink absorbency and extremely low ink drying rate. Moreover, acidic (meth)acrylic polymers show bad compatibility with PVP and therefore, when mixed with PVP, they present drawbacks that it is difficult to obtain uniform coatings and it is difficult to adjust physical properties of coatings.
When designing ink-receiving layers of recording materials for ink-jet printing, ink absorption and retention properties had been considered with respect only to aqueous inks. But, there have recently been proposed certain materials comprising hydrophilic and hydrophobic resins in ink-receiving layers, thereby these materials can be used for ink-jet printing and PPC (electrophotographic copiers) in common (Japanese Patent Un-examined Publication (KOKAI) No. 5-177921). The ink-receiving layers of these kinds of recording paper are made have toner adhesion in addition to absorbency with respect to aqueous inks and water resistance. However, any recording paper which may be more widely used, i.e., which may also be used for direct thermal transfer printing, pen plotter printing and the like has not been proposed yet.